User interface for a portion of a display screen



FIG. 1 is a front view of a user interface for a portion of a display screen showing our new design; and,

FIG. 2 is a front view thereof, on an enlarged scale, the claimed portion of the user interface is shown separately for clarity of illustration.

The broken line showing of the regions within the claimed design and the area within those regions forms no part of the claimed design. The broken line showing of the portion of a display screen is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a user interface for a portion of a display screen, as shown and described. 